MX2007013705A - Fiber reinforced polypropylene compositions - Google Patents

Abstract

The present invention is directed generally to fiber reinforced polypropylene compositions, and the beneficial mechanical properties imparted by such compositions. The fiber reinforced polypropylene compositions include at least 25 wt%polypropylene based polymer, from 5 to 60 wt%organic fiber, and from O to 60 wt%inorganic filler. Lubricant may also be optionally incorporated into the composition. Articles molded from these fiber reinforced polypropylene compositions have a flexural modulus of at least 300,000 psi, and exhibit ductility during instrumented impact testing. The fiber reinforced polypropylene compositions of the present invention are particularly suitable for making molded articles including, but not limited to household appliances, automotive parts, and boat hulls.

Description

REINFORCED POLYPROPYLENE COMPOSITIONS WITH FIBERS FIELD OF THE INVENTION The present invention is generally directed to articles made of fiber reinforced polypropylene compositions having a flexural modulus of at least 21090 kg / cm2 and exhibiting ductility during instrumented impact testing. The present invention is also directed to processes for forming said articles. More particularly, it relates to advantageous fiber reinforced polypropylene material compositions. Even more particularly, the present invention relates to mixed fiber materials based on polypropylene, an organic fiber and an inorganic filler. BACKGROUND OF THE INVENTION Polyolefins have limited use in engineering applications due to the exchange between hardness and rigidity. For example, polyethylene is widely considered to be relatively hard, but low in rigidity. Polypropylene generally exhibits the opposite tendency, that is, it is relatively rigid but with low hardness. Several well-known polypropylene compositions have been introduced which provide hardness.

For example, it is known to increase the hardness of polypropylene by adding rubber particles, either within the reactor resulting in impact copolymers or by mixing after the reactor. However, while the hardness is improved, the stiffness is considerably reduced using this approach. Glass-reinforced polypropylene compositions have been introduced to improve stiffness. However, glass fibers have a tendency to force the typical injection molding equipment, resulting in reduced hardness and rigidity. In addition, reinforced glass products have a tendency to be wrapped after the model by injection. Another known method for improving the physical properties of polyolefins is the reinforcement of organic fibers. For example, Patent Application EP 0397881, the entire disclosure of which is incorporated herein by reference, discloses a composition produced by melt blending of 100 parts by weight of a polypropylene resin and 10 to 100 parts by weight of fibers. of polyester having a fiber diameter of 1 to 10 deniers, a fiber length of 0.5 to 50 mm and a fiber strength of 5 to 13 g / d, and then molding the resulting mixture. Also, the U.S. Patent. 3,639,424 to Gray, Jr. and others, the entire disclosure of which is incorporated herein by reference, discloses a composition that includes a polymer, such as polypropylene and uniformly dispersed therein at least about 10% by weight of the fiber of base length, the fiber being man-made polymers such as polyethylene terephthalate or poly (1,4-cyclohexylenedimethylene) terephthalate. The fiber reinforced polypropylene compositions are also described in PCT Publication WO 02/053629 discloses a polymeric composite, comprising a thermoplastic matrix having a high flux during the melting process and polymer fibers having lengths from 0.1 mm to 50 mm. mm. The polymeric compound comprises between 0.5% by weight and 10% by weight of a lubricant. Various modifications of polypropylene compositions reinforced with organic fibers are also known. For example, polyolefins modified with anhydride or acrylic acid have been used as the matrix component to improve the interfacial strength between the synthetic organic fiber and the polyolefin, which was thought to improve the mechanical properties of the molded product made thereof. Other background references include PCT Publication WO 90/05164; Patent Application EP 0669371; Patent of E.U.A. No. 6,395,342 to Kadowaki et al .; Patent Application EP 1075918; Patent of E.U.A. Do not. ,145,891 to Yasukawa et al., U.S. Patent 5,146,892 to Yasukawa et al .; and EP 0232522, all descriptions incorporated herein by reference. There is a need for a mixed fiber material based on improved polypropylene which gives a combination of improved impact strength / hardness, and rigidity for use in molded articles at favorable raw material and manufacturing costs. In addition, polypropylene fiber compositions when formed into molded articles will ideally not splinter after being ruptured by drop test by their own weight.

SUMMARY OF THE INVENTION Surprisingly it has been found that polypropylene compositions reinforced with fibers substantially free of lubricants can be formed which simultaneously have a flexural modulus of at least 21090 kg / cm2 and exhibit ductility during the instrumented impact test. Particularly surprising is the ability to form such compositions using a broad scale of polypropylenes as the matrix material, including some polypropylenes which without fiber are very fragile. The compositions of the present invention are particularly suitable for forming articles including, but not limited to, household appliances, automotive parts, and boat hulls. In one embodiment, the present invention provides an article of manufacture made from a composition that compresses, based on the total weight of the composition, at least 30% by weight of polypropylene, from 10 to 60% by weight of organic fiber, 0 to 40% by weight of inorganic filler and from 0 to 0.1% by weight of lubricant. The composition has a flexural modulus of at least 21090 kg / cm2 and exhibits ductility during the instrumented impact test (24.141 km / hr, -29 ° C, 11.34 kg). In another embodiment, the mixed material of fiber reinforced polypropylene with an inorganic filler further includes 0.01 to 0.1% by weight of lubricant. Suitable lubricants include, but are not limited to, silicone oil, silicone gum, fatty amide, paraffin oil, paraffin wax, and ester oil. In another embodiment, the present invention provides an automotive part made of said composition. In another embodiment, the present invention provides an article of ready manufacture of a composition consisting essentially of at least 30% by weight of homopolypropylene, from 10 to 60% by weight of organic fiber and from 0.1 to 40% by weight of filler inorganic, based on the total weight of the composition. The composition has a flexural modulus of at least 21090 kg / cm2 and exhibits ductility during instrumented impact testing (24,141 km / hr, -29 ° C, 11.34 kg). In yet another embodiment, the present invention provides a process for forming an automotive part. The process comprises extrusion forming a composition to form an extrudate and injection molding the extrudate to form the automotive part. The composition used to form the extrudate comprises at least 30% by weight of polypropylene, from 10 to 60% by weight of organic fiber, from 0 to 40% by weight of inorganic filler, and from 0 to 0.21% by weight of lubricant . The composition has a flexural modulus of at least 21090 kg / cm2 and exhibits ductility during instrumented impact testing (24,141 km / hr, -29 ° C, 11.34 kg). In yet another embodiment of the present disclosure, it provides an advantageous polypropylene resin composition comprising at least 30% by weight, based on the total weight of the composition, polypropylene; from 10 to 60% by weight based on the total weight of the composition, organic fiber; from 0 to 40% by weight, wherein the molded article of said composition has a flexural modulus of at least 21090 kg / cm 2 and exhibits ductility during instrumented impact testing (24,141 km / hr, -29 ° C, 11.34 kg ). In yet another embodiment of the present disclosure provides an advantageous polypropylene resin composition comprising at least 25% by weight based on the total weight of the composition, polypropylene based polymer with a melt flow rate of about 20 to about of 1500 g / 10 minutes; from 5 to 40% by weight, based on the total weight of the composition, organic fiber; and from 10 to 60% by weight, based on the total weight of the composition, inorganic filler; wherein a molded article of said composition has a flexural modulus of at least about 21090 kg / cm 2 and exhibits ductility during instrumented impact testing (24,141 km / hr, -29 ° C, 11.34 kg). In yet another embodiment of the present disclosure provides an advantageous polypropylene resin composition comprising at least 30% by weight based on the total weight of the composition, polypropylene based polymer, from 5 to 40% by weight, based on the total weight of the composition, organic fiber; from 10 to 60% by weight, based on the total weight of the composition, inorganic filler; and from 0.01 to 0.1% by weight based on the total weight of the composition, lubricant; wherein a molded article of said composition has a flexural modulus of at least about 21090 kg / cm2 and exhibits ductility during instrumented impact testing. In still another embodiment of the present disclosure, it provides an advantageous polypropylene resin composition comprising at least 25% by weight based on the total weight of the polypropylene-based polymer composition, wherein the polypropylene-based polymer has melt flow of at least 80 g / 10 minutes; from 5 to 15% by weight based on the total weight of the composition, organic fiber; and from 50 to 60% by weight based on the total weight of the composition, talc or volastonite; wherein a molded article of the composition has a flexural modulus of at least about 52725 kg / cm 2 and exhibits ductility during instrumented impact testing (24,141 km / hr, -29 ° C, 11.34 kg). In still another embodiment of the present disclosure an advantageous polypropylene resin composition is provided comprising at least 40% by weight, based on the total weight of the composition, polypropylene-based polymer, wherein the polypropylene-based polymer has a melt flow rate of at least 100 g / 10 minutes; from 10 to 30% by weight based on the total weight of the composition, organic fiber; and from 10 to 30% by weight based on the total weight of the composition, talc or volastonite; wherein a molded article of said composition has a flexural modulus of at least about 22847.5 kg / cm2 and exhibits ductility during uncreated impact testing (24.141 km / hr, -29 ° C, 11.34 kg).

Numerous advantages result from the mixed materials of advantageous polypropylene fibers, the training method described herein and uses / applications thereof. For example, in illustrative embodiments of the present disclosure, the mixed polypropylene fiber materials disclosed exhibit improved instrumented impact strength. In a further illustrative embodiment of the present disclosure, the mixed polypropylene fiber materials described exhibit improved flexural modulus. In a further illustrative embodiment of the present disclosure, the mixed polypropylene fiber materials described are not assigned during the instrumented impact test. In yet a further illustrative embodiment of the present disclosure, the mixed polypropylene fiber materials described exhibit fiber extraction during the impact test instrumented without the need for lubricating additives. In still a further illustrative embodiment of the present disclosure, the mixed polypropylene fiber materials described exhibit a distortion temperature compared to rubber-hardened polypropylene.

In yet a further illustrative embodiment of the present disclosure, the mixed polypropylene fiber materials disclosed exhibit a lower linear coefficient of thermal flow and counterflow compared to rubber-hardened polypropylene. These and other advantages, aspects and attributes of the mixed polypropylene fiber materials and method for creating the present disclosure and its applications and / or advantageous uses will be apparent from the following detailed description, particularly when read together with the accompanying figures. to the same.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to polypropylene compositions reinforced with improved fibers and method for forming same for use in molding applications. The fiber reinforced polypropylene compositions of the present invention are distinguished from the prior art in that they comprise a combination of a matrix based on polypropylene with organic fiber and inorganic filler, which in combination advantageously produce molded articles of the compositions with a flexural modulus. of at least 21090 kg / cm2 and ductility during instrumented impact test (24.141 km / hr, -29 ° C, 11.34 kg). The fiber reinforced polypropylene compositions of the present invention can also be distinguished from the prior art since they comprise a polypropylene based polymer with an advantageous high melt flow rate without sacrificing impact strength. In addition, the fiber reinforced polypropylene compositions of the present invention do not splinter during the instrumented impact test. The fiber reinforced polypropylene compositions of the present invention simultaneously have desirable stiffness, measured having a flexural modulus of at least 21090 kg / cm2, and hardness, as measured by the ductility exhibited during the instrumented impact test. In a particular embodiment, the compositions have a flexural modulus of at least 24605 kg / cm2, or at least 26011 kg / cm2, or at least 27417 kg / cm2, or at least 28120 kg / cm2, or by at least 31635 kg / cm2. Even more particularly, the compositions have a flexural modulus of at least 42180 kg / cm2 or at least 56240 kg / cm2. It is also thought that having a weak interface between the polypropylene matrix and the fiber contributes to the extraction of the fiber; and, therefore, can improve the hardness. Therefore, it is not necessary to add modified polypropylenes to improve the bond between the organic fiber and the polypropylene matrix, although the use of modified polypropylene may be advantageous to improve the bond between a filler such as talc or volastonite and the matrix. Furthermore, in one embodiment, it is not necessary to add lubricant to weaken the interface between the polypropylene and the organic fiber to further improve the extraction of the fibers. Some modalities also do not exhibit splintering during the instrumented dart impact test, which gives it an additional advantage by not subjecting a person in close proximity to the impact to splinters that potentially damage. The compositions of the present invention generally include at least 30% by weight, based on the total weight of the composition, of polypropylene as the matrix resin. In a particular embodiment, the polypropylene is present in an amount of at least 30% by weight, or at least 35% by weight, or at least 40% by weight, or at least 45% by weight, or by at least 50% by weight, or in an amount within the scale that has a lower limit of 30% by weight, or 35% by weight, or 40% by weight or 45% by weight or 50% by weight, or a upper limit of 75% by weight, or 80% by weight, based on the total weight of the composition. In another embodiment, the polypropylene is present in an amount of at least 25% by weight. The polypropylene used as the matrix resin is not particularly restricted and is generally selected from the group consisting of propylene homopolymers, random propylene-ethylene copolymers, random propylene-to-olefin copolymers, propylene block copolymers, impact copolymers of propylene, and their combinations. In a particular embodiment, the polypropylene is a homopolymer of propylene. In another particular embodiment, the polypropylene is a propylene impact copolymer comprising from 78 to 95% by weight of homopolypropylene and from 5 to 22% by weight of ethylene-propylene rubber, based on the total weight of the impact copolymer. In a particular aspect of this embodiment, the propylene impact copolymer comprises from 90 to 95% by weight of homopolypropylene and from 5 to 10% by weight of ethylene-propylene rubber, based on the total weight of the impact copolymer. The polypropylene of the matrix resin can have a melt flow rate of about 20 to about 1500 g / 10 min. In a particular embodiment, the melt flow rate of the polypropylene matrix resin is greater than 100 g / 10 min, and even more particularly greater than or equal to 400 g / 10 min. In yet another embodiment, the melt flow rate of the polypropylene matrix resin is about 1500 g / 10 min. The superior melt flow regime allows process improvements, performance regimes and higher organic fiber and inorganic filler loading levels without negatively impacting the flexural modulus and impact resistance.

In a particular embodiment, the matrix polypropylene contains less than 0.1% by weight of a modifier, based on the total weight of the polypropylene. Normal modifiers include, for example, unsaturated carboxylic acids, such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid or esters thereof, maleic anhydride, itaconic anhydride and derivatives thereof. In another particular embodiment, the matrix polypropylene does not contain a modifier. In yet another particular embodiment, the polypropylene-based polymer further includes about 0.1% by weight of less than about 10% by weight of a polymer based on polypropylene modified with a grafting agent. The grafting agent includes, but is not limited to, acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid or esters thereof, maleic anhydride, itaconic anhydride and combinations thereof. The polypropylene may further contain additives commonly known in the art, such as dispersant, lubricant, flame retardant, antioxidant, antistatic agent, light stabilizer, ultraviolet light absorber, carbon black, nucleating agent, plasticizer and coloring agent such as colorant. or pigment. The amount of additive, if present, in the polypropylene matrix is generally 0.5% by weight or 2.5% by weight, 7.5% by weight, or 10% by weight, based on the total weight of the matrix. The diffusion of the additives during the process can cause a portion of the additives to be present in the fiber. The invention is not limited by any particular polymerization method to produce the matrix polypropylene and the polymerization processes described herein are not limited by any particular type of reaction vessel. For example, the matrix polypropylene can be produced using any of the well known polymerization processes of slurry polymerization solution, bulk polymerization, gas phase polymerization and combinations thereof. In addition, the invention is not limited to any particular catalyst to form the polypropylene, and for example, may include Ziegler-Natta or metallocene catalysts. The compositions of the present invention generally include at least 10% by weight, based on the total weight of the composition, of an organic fiber. In a particular embodiment, the fiber is present in an amount of at least 10% by weight, or at least 15% by weight, or at least 20% by weight, or in an amount within the scale that has a lower limit of 10% by weight, or 15% by weight, or 20% by weight and an upper limit of 50% by weight, or 55% by weight, or 50% by step or 70% by weight, based on weight total of the composition. In another embodiment, the organic fiber is present in an amount of at least 5% by weight and up to 40% by weight. The polymer used as the reinforcing fiber is not particularly restricted and is generally selected from the group consisting of polyalkylene terephthalates, polyalkylene naphthalates, polyamides, polyolefins, polyacrylonitrile and combinations thereof. In a particular embodiment, the fiber comprises a polymer selected from the group consisting of polyethylene terephthalate PET), polybutylene terephthalate, polyamide and acrylic. In another particular embodiment, the organic fiber comprises PET. In one embodiment, organic fiber is a single component fiber. In another embodiment, fiber is a multi-component fiber wherein the fiber is formed from a process wherein the fiber is formed from a process wherein at least two polymers are extruded from separate extruders and blown by melting or centrifuged together to form a fiber In a particular aspect of this embodiment, the polymers used in the multi-component reinforcing fiber are substantially the same. In another particular aspect of this embodiment, the polymers used in the multi-component reinforcing fiber are different from each other. The configuration of the multi-component reinforcing fiber can be, for example, a deck / core arrangement, a side-by-side arrangement, a standing arrangement, an arrangement of islands in the sea, or a variation thereof. The reinforcing fiber can also be removed to improve the mechanical properties via orientation and subsequently anneal at elevated temperatures, but below the crystalline melting point to reduce shrinkage and improve dimensional stability at elevated temperature. The length and diameter of the fibers of the present invention are not particularly restricted. In a particular embodiment, the fibers have a length of 6.35 mm, or a length within the scale having a lower limit of 3,175 mm, or 4 mm, and an upper limit of 7.62 mm or 12.7 mm. In another particular embodiment, the diameter of the fibers is within the scale that has a limit of less than 10 μm and an upper limit of 100 μm. The fiber may further contain additives commonly known in the art, such as dispersant, lubricant, flame retardant, antioxidant, antistatic agent, light stabilizer, ultraviolet light absorber, carbon black, nucleating agent, plasticizer, and coloring agent such as dye or pigment. The fiber used to form the compositions of the present invention is not limited by any particular fiber form. For example, the fiber may be in the form of continuous filament yarn, partially oriented yarn, or basic fiber. In another embodiment, the fiber can be a continuous multi-filament fiber or a continuous monofilament fiber. The compositions of the present invention optionally include inorganic filler in an amount of at least 1% by weight, or at least 5% by weight, or at least 10% by weight, or in an amount within the scale that has a lower limit of 0% by weight, or 1% by weight, or 5% by weight, or 10% by weight, 15% by weight and an upper limit of 25% by weight, or 30% by weight, or 35% by weight or 40% by weight, based on the total weight of the composition. In yet another embodiment, the inorganic filler may be included in the mixed polypropylene fiber material in the range of 120 wt% to about 60 wt%. In a particular embodiment, the inorganic filler is selected from the group consisting of talc, calcium carbonate, calcium hydroxide, barium sulfate, mica, calcium silicate, clay, kaolin, silica, alumina, volastonite, magnesium carbonate, hydroxide of magnesium, titanium oxide, zinc oxide, zinc sulfate, and combinations thereof. The talc can have a size of about 1 to about 100 microns. In a particular embodiment, a high talc load of up to about 60% by weight, the mixed polypropylene fiber material exhibited a flexural modulus of at least about 52725 kg / cm2, and does not splinter during the instrumented impact test. (15 rph, -29 ° C, 11.34 kg). In another particular embodiment, at a low talc load of as low as 10% by weight, the mixed material of polypropylene fibers exhibited a flexural modulus of at least about 22847.5 kg / cm2 and did not splinter during the impact test instrumented (15 rph, -29 ° C, 11.34 kg). In addition, the volastonite faces of 10 wt% to 60 wt% in the mixed polypropylene fiber material gave an outstanding combination of impact resistance and stiffness. In another particular embodiment, a fiber reinforced polypropylene composition includes a polypropylene-based resin with a melt flow rate of from 80 to 1500, from 10 to 15% by weight of polyester fiber and from 50 to 60% by weight of the Inorganic filler exhibited a flexural modulus of 59755 to 84360 kg / cm2 and is not destroyed during the instrumented impact test at -20 degrees Celsius, tested at 11.34 kg and 6.706 M / sec. The inorganic filler includes, but is not limited to, talc and volastonite. This combination of stiffness and hardness is difficult to achieve in a polymer-based material. further, the fiber reinforced polypropylene composition has a heat distortion temperature of 4.64 kg / cm2 of 140 degrees Celsius and a coefficient of flow and counterflow of linear thermal expansion of 2.2 x 10"5 and 3.3 x 10" 5 per degree centigrade respectively. In comparison, rubber-hardened polypropylene has a heat distortion temperature of 94.6 degrees centigrade and a coefficient of thermal expansion of flow and counterflow of 10 x 10"5 and 18.6 x 10" 5 per degree centigrade respectively. The articles of the present invention are made by forming the polypropylene composition reinforced with fibers in a resin and then injection molding the resin composition to form the article. To achieve a surface feel in the article, the surface of the mold can also have a textured surface. The invention is not limited to any particular method for forming the compositions. For example, the compositions may be formed by contacting the polypropylene, organic reinforcing fiber, dye fiber and optional inorganic filler in any of the well-known processes of compounding by pultrusion or extrusion. In a particular embodiment, the compositions are formed in a compounding process by extrusion. In a particular aspect of this embodiment, the organic fibers are cut before being placed in the extruder hopper. In another particular aspect of this embodiment, the organic fibers are fed directly from one or more coils into the extruder hopper. Articles made from the compositions described herein include, but are not limited to automotive parts, household appliances, and boat hulls. The present invention is further illustrated by means of the following examples and the advantages thereof without limiting the scope thereof.

Test Methods The fiber reinforced polypropylene compositions described herein were injection molded at a pressure of 161.69 kg / cm2, 401 ° C to all heating zones as well as the nozzle, with a mold temperature of 60 ° C. Bending module data was generated for injected molded samples produced from the fiber reinforced polypropylene compositions described herein using the standard ISO 178 method. The instrumented impact test data was generated for injected mold samples produced from the fiber reinforced polypropylene compositions described herein using ASTM D3763. The ductility during the instrumented impact test (test conditions of 24,141 km / hr, -29 ° C, 11.34 kg) is defined by not chipping the sample.

Examples PP3505G is a propylene homopolymer commercially available from Exxon Mobil Chemical Company of Baytown, Texas. The MFR (2.16 kg, 230 ° C) of PP3505G is measured according to ASTM D1238 to be 400 g / 10 min. PP7805 is an 80 MFR propylene impact copolymer commercially available from Exxon Mobil Chemical Company of Baytown, Texas. PP8114 is a propylene impact copolymer of 22 MFR containing ethylene-propylene rubber and a plastomer and is commercially available from Exxon Mobil Chemical Company of Baytown, Texas. PP8224 is a 25 MFR propylene impact copolymer containing ethylene-propylene rubber and a plastomer and is commercially available from Exxon Mobil Chemical Company of Baytown, Texas. PO1020 is a functionalized polypropylene maleic anhydride homopolymer of 430 MFR containing maleic anhydride of 0.5-1.0 weight percent. Cimpact CB7 is a talc modified on its surface and V3837 is a talc with high aspect ratio, available from Luzenac America Inc. of Englewood, Colorado.

Illustrative examples 1-8 Variable amounts of PP3505G and 6.35 mm long polyester fibers obtained from Invista Corporation were mixed where they were mixed in a Haake single screw extruder at 175 ° C. The strand exiting the extruder was cut into 12.7 mm lengths and injection molded using a Boy injection moulder of 45.3 kg at 205 ° C in a mold maintained at 60 ° C. Injection pressures and nozzle pressures were maintained at 161.69 kg. Samples were molded according to the geometry of ASTM D3763 and tested for instrumented impact under normal automotive conditions for interior parts (11.34 kg, at 24,141 km / hr, at -29 ° C). The total results of energy absorbed from impact are given in Table 1. Table 1 * Examples 1-6: Samples do not splinter or split as a result of impact, without specimen parts coming out. ** Example 7: the pieces are separated from the sample as a result of the impact *** Example 8: the samples are completely splintered as a result of the impact.

Illustrative Examples 9-14 In Examples 9-11, 35% by weight of PP7805, 20% by weight of Cimpact CB7 talc, and 45% by weight of 6.35 mm long polyester fibers from Invista Corporation, were mixed in a Haake twin screw extruder at 175 ° C. The strand exiting the extruder was cut into 12.7 mm lengths and injection molded using a Boy injection moulder of 49985.618 kg at 205 ° C in a mold maintained at 60 ° C. The injection pressures and nozzle pressures were maintained at 161.69 kg / cm2. The samples were molded according to the geometry of ASTM D3763 and tested for instrumented impact. The results of total energy absorbed and impact are given in Table 2. In Examples 12-14, PP8114 was extruded and injection molded under the same conditions as those for Examples 9-11. The total energy absorbed and the impact results are given in Table 2.

Table 2 * Examples 9-12: Samples were not splintered or divided as a result of impact, without specimen parts being loosened. ** Examples 13-14: Samples were splintered as a result of impact.

Illustrative examples 15-16 A Leistritz 27 mm twin screw extruder ZSE27 HP-60D with a length-to-diameter ratio of 40: 1 was adapted with six pairs of 30.48 cm kneading elements from the die output. The die was 6.35 mm in diameter. The 27,300 denier PET reinforcement fiber strands were fed directly from the coils into the extruder hopper, along with PP7805 and talc. The kneading elements in the extruder separated the fiber in situ. The speed of the extruder was 400 revolutions per minute and the temperatures through the extruder were maintained at 190 ° C. Injection molding was performed under conditions similar to those described for Examples 1-14. The mechanical and physical properties of the sample were measured and compared in Table 3 with the mechanical and physical properties of PP8224. The instrumented impact test showed that in both examples there was no evidence of splitting or chipping, without the pieces leaving the specimen. In the Charpy test with notches, the specimen of PP7805 reinforced with fibers of PET only partially separated and specimen PP8224 completely separated. Table 3 Test Example 15 Example 16 (Method) Fiber-reinforced PET PP8224 of PP7805 with talc Flex Module, rope 36920.857 Kg / c2 11223.044 Kg / cm2 (ISO 178) Instrumented Impact at -30 ° C 6.8 Joules 27.5 Joules Maximum load power 45.35 kg to 5MPH (ASTM D3763) Impact of Charpy with notches a- 52.4 KJ / m2 5.0 KJ / m2 40 ° C (ISO 179 / leA) Temperature of Deflection by Heat 116.5 ° C 97.6 ° CA 0.45 MPa, by the shore (IS075) ) Thermal Expansion Coefficient 2.2 / 12.8 10.0 / 18.6 Linear, -30 ° C to 100 ° C, (E-5 / ° C) (E-5 / ° C) Flow / Contraflu (ASTM E831) Illustrative Examples 17- In Examples 17-18, 30% by weight of PP3505G or PP8224, 15% by weight of fibers with 6.35 m long polyester obtained from Invista Corporation, and 45% by weight of talc V3837 were mixed in a screw extruder double Haake at 175 ° C. The strand exiting the extruder was cut into rare 12.7 lengths and injection molded using a Boy injection moulder of 49985.618 kg at 205 ° C in a mold maintained at 60 ° C. The injection pressures and nozzle pressures were maintained at 161.69 kg / cm3. Samples were molded according to the geometry of ASTM D3763 and tested for flexural modulus. The results of the flexural modulus are given in the Table.

Table 4 The PP8114 matrix hardened with rubber with PET and talc fibers exhibited lower impact values than PP3505 homopolymer. This result is surprising, because the rubber-hardened matrix alone is much harder than the low molecular weight PP3505 homopolymer only at all temperatures under any impact condition. In both previous examples, the materials did not exhibit chipping.

Illustrative examples 19-24 In Examples 19-24, 25-75% by weight PP3505G, 15% by weight of 6.35 mm long polyester fibers obtained from Invista Corporation, and 10-60% by weight of talc V3837 were mixed in the double extruder Haake screw at 175 ° C. The strand exiting the extruder was cut into 12.7 mm lengths and injection molded using a Boy injection moulder of 49985.618 kg at 205 ° C in a mold maintained at 60 ° C. The injection pressures and nozzle pressures were maintained at 161.69 kg / cm2. Samples were molded according to the geometry of ASTM D3763 and tested for flexural modulus. The results of the flexural modulus are given in Table 5.

Table 5 It is important to note that in Examples 19-24, the samples did not exhibit chipping in the weight drop test at -29 ° C, 24,141 km / hr at 11.34 kg.

Illustrative Examples 25-26 Two materials, one containing 10% 6.35 mm polyester fibers, 35% polypropylene PP3505 and 60% talc V3837 (example 25), the other containing 10% 6.35 mm polyester fibers, 25% PP3505 polypropylene homopolymer (example 26), 10% PO1020 modified polypropylene were molded in a Haake twin screw extruder at 175 ° C. They were injection molding on tension specimens of the 12.7mm normal width ASTM A370 sheet type. The specimens were tested in tension, with a minimum to maximum load ratio of 0.1, at bending stresses of 70 and 80% of the maximum tension.

Table 6 The addition of the modified polypropylene is shown to increase the fatigue life of these materials.

All patents, test procedures and other documents cited herein, including priority documents, are fully incorporated by reference to the degree that said description is not inconsistent with this invention and for all jurisdictions in which incorporation is permitted. While the illustrative embodiments of the invention have been described with particularity, it will be understood that various other modifications will be apparent and can easily be made by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is not intended that the scope of the claims appended thereto be limited to the examples and descriptions herein, but that the claims be construed as encompassing all aspects of patentable novelty that reside in the invention, including all aspects thereof. they could be treated as equivalents thereof by those skilled in the art to which the invention pertains. When the numerical lower limits and upper numerical limits are listed herein, variations of any lower limit to any upper limit are contemplated.

Claims (44)

1. - A polypropylene resin composition comprising: (a) at least 30% by weight based on the total weight of the composition, polypropylene-based polymer; (b) from 10 to 15% by weight based on the total weight of the composition, organic fiber chosen from polyalkylene terephthalates, polyalkylene naphthalates and combinations thereof; and (c) from 0 to 40% by weight based on the total weight of the composition, inorganic filler; wherein said composition is substantially free of lubricant; wherein a molded article of said composition has a flexural modulus of at least 2068 GPa and exhibits ductility during instrumented impact testing.

2. - The polypropylene resin composition of claim 1, wherein the polypropylene-based polymer is selected from the p consisting of polypropylene homopolymers, propylene-ethylene random copolymers, propylene-to-olefin random copolymers, copolymers of impact of propylene and its combinations.

3. - The polypropylene resin composition of claim 2, wherein said polypropylene-based polymer is polypropylene homopolymer.

4. - The polypropylene resin composition of claim 1, wherein the polypropylene-based polymer further comprises about 0.01% by weight to less than about 0.1% by weight of a modifier selected from the p consisting of acrylic acid, acid methacrylic, maleic acid, itaconic acid, fumaric acid or esters thereof, maleic anhydride, itaconic anhydride and combinations thereof.

5. - The polypropylene resin composition of claim 1, wherein said organic fiber is randomly dispersed within said polypropylene-based polymer.

6. - The polypropylene resin composition of claim 5, wherein the organic fiber is a polyalkylene terephthalate.

7. - The polypropylene resin composition of claim 6, wherein the organic fiber is polyethylene terephthalate.

8. - The polypropylene resin composition of claim 1, wherein said inorganic filler is selected from the p consisting of talc, calcium carbonate, calcium hydroxide, barium sulfate, mica, calcium silicate, clay, kaolin, silica, alumina, volastonite, magnesium carbonate, magnesium hydroxide, titanium oxide, zinc oxide, zinc sulfate, and combinations thereof.

9. - The polypropylene resin composition of claim 8, wherein the inorganic filler is talc or volastonite.

10. - The polypropylene resin composition of claim 1, wherein the molded article of said composition has a flexural modulus of at least 3.103 GPa.

11. - A polypropylene resin composition comprising: (a) at least 25% by weight based on the total weight of the composition, polymer based on polypropylene with a melt flow rate of about 20 to about 1500 g /10 minutes; (b) from 5 to 15% by weight based on the total weight of the composition, organic fiber chosen from polyalkylene terephthalates, polyalkylene naphthalates and combinations thereof; and (c) from 10 to 60% by weight based on the total weight of the composition, inorganic filler; wherein said composition is substantially free of lubricants; wherein the molded article of the composition has a flexural modulus of at least about 2068 GPa and exhibits ductility during instrumented impact testing.

12. The polypropylene resin composition of claim 11, wherein said polypropylene-based polymer is selected from the p consisting of polypropylene homopolymers, random copolymers of propylene-ethylene, random copolymers of propylene-to-olefin, copolymers of impact of propylene, and their combinations.

13. - The polypropylene resin composition of claim 12, wherein the polypropylene-based polymer is polypropylene homopolymer with a melt flow rate of from about 150 to about 1500 g / 10 minutes.

14. - The polypropylene resin composition of claim 11, wherein the polypropylene-based polymer further comprises about 0.1% by weight or less than about 10% by weight of a polymer based on polypropylene modified with a grafting agent, wherein the grafting agent is selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid or esters thereof, maleic anhydride, itaconic anhydride, and combinations thereof.

15. - The polypropylene resin composition of claim 11, wherein the organic fiber is randomly dispersed within said polypropylene-based polymer.

16. - The polypropylene resin composition of claim 15, wherein the organic fiber is a polyalkylene terephthalate.

17. - The polypropylene resin composition of claim 16, wherein the organic fiber is polyethylene terephthalate at a loading of about 7.5% to about 15% by weight.

18. - The polypropylene resin composition of claim 11, wherein said inorganic filler is selected from the group consisting of talc, calcium carbonate, calcium hydroxide, barium sulfate, mica, calcium silicate, clay, kaolin, silica, alumina, volastonite, magnesium carbonate, magnesium hydroxide, titanium oxide, zinc oxide, zinc sulfate, and combinations thereof.

19. - The polypropylene resin composition of claim 18, wherein said inorganic filler is talc or volastonite at a loading of about 20% to about 60% by weight.

20. - The polypropylene resin composition of claim 19, wherein the size of said talc is from about 1 to about 100 microns.

21. - The propylene resin composition of claim 11, wherein said molded article of said composition has a flexural modulus of at least about 4,137 GPa.

22. The propylene resin composition of claim 11, wherein the molded article of said composition has a flexural modulus of at least about 6,895 GPa.

23. A polypropylene resin composition comprising: (a) at least 30% by weight based on the total weight of the composition, polypropylene-based polymer; (b) from 5 to 15% by weight, based on the total weight of the composition, organic fiber chosen from polyalkylene terephthalates, polyalkylene naphthalates and combinations thereof; (c) from 10 to 60% by weight, based on the total weight of the composition, inorganic filler; and (d) from 0.01 to 0.1% by weight, based on the total weight of the composition, modifier; wherein said composition is substantially free of lubricants; wherein said molded article of the composition has a flexural modulus of at least about

3. 103 GPa and exhibits ductility during instrumented impact testing.

24. - The polypropylene resin composition of claim 23, wherein the modifier is selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid or esters thereof, malic anhydride, itaconic anhydride and its combinations.

25. - The polypropylene resin composition of claim 23, wherein the polypropylene based polymer is polypropylene homopolymer.

26. - The polypropylene resin composition of claim 23, wherein the organic fiber is randomly dispersed within the polypropylene-based polymer.

27. The polypropylene resin composition of claim 26, wherein the organic fiber is polyethylene terephthalate.

28. - The polypropylene resin composition of claim 27, wherein the inorganic filler is talc or volastonite.

29. - A polypropylene resin composition comprising: (a) at least 25% by weight, based on the total weight of the composition, polypropylene-based polymer, wherein the polypropylene-based polymer has melt flow rate of at least 80 g / 10 minutes; (b) from 5 to 15% by weight, based on the total weight of the composition, organic fiber chosen from polyalkylene terephthalates, polyalkylene naphthalates and combinations thereof; and (c) from 50 to 60% by weight, based on the total weight of the composition, talc or volastonite; wherein said composition is substantially free of lubricant; wherein a molded article of said composition has a flexural modulus of at least about 5,171 GPa and exhibits ductility during instrumented impact testing.

30. The polypropylene resin composition of claim 29, wherein the polypropylene-based polymer is selected from the group consisting of polypropylene homopolymers, propylene-ethylene random copolymers, propylene-to-olefin random copolymers, propylene impact copolymers, and combinations thereof.

31. The polypropylene resin composition of claim 30, wherein the polypropylene-based polymer is polypropylene homopolymer with a melt flow rate of at least about 400 g / 10 minutes.

32. - The polypropylene resin composition of claim 29, wherein the polypropylene-based polymer further comprises about 0.1 wt% to less than about 10 wt% of a polymer based on polypropylene modified with a grafting agent, wherein the grafting agent is selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid or esters thereof, maleic anhydride, itaconic anhydride and combinations thereof.

33. - The polypropylene resin composition of claim 29, wherein the organic fiber is randomly dispersed within the polypropylene-based polymer.

34. The polypropylene resin composition of claim 33, wherein the organic fiber is selected from the group consisting of polyalkylene terephthalates, polyalkylene naphthalates, polyamides, polyolefins, polyacrylonitrile, and combinations thereof.

35.- The polypropylene resin composition of claim 34, wherein the organic fiber is polyethylene terephthalate.

36.- The polypropylene resin composition of claim 35, wherein the size of talc is from 1 to about 100 microns.

37. - The polypropylene resin composition of claim 36, wherein the molded article of the composition has a flexural modulus of at least about 6,895 GPa.

38. A polypropylene resin composition comprising: (a) at least 40% by weight, based on the total weight of the polypropylene-based polymer composition, wherein said polypropylene-based polymer has a flow rate of fusion of at least 100 g / 10 minutes; (b) from 10 to 15% by weight, based on the total weight of the composition, organic fiber chosen from polyalkylene terephthalates, polyalkylene naphthalates and combinations thereof; and (c) from 10 to 30% by weight based on the total weight of the composition, talc or volastonite; wherein the composition is substantially free of lubricant; wherein a molded article of the composition has a flexural modulus of at least about 2,241 GPa and exhibits ductility during instrumented impact testing.

39.- The polypropylene resin composition of claim 38, wherein the polypropylene-based polymer is selected from the group consisting of polypropylene homopolymers, random copolymers of propylene-ethylene, random copolymers of propylene-α-olefin, copolymers of impact of propylene and its combinations.

40.- The polypropylene resin composition of claim 39, wherein the polypropylene-based polymer is polypropylene homopolymer with a melt flow rate of at least about 400 g / 10 minutes.

41. The polypropylene resin composition of claim 38, wherein the polypropylene-based polymer further comprises about 0.1% by weight to less than about 10% by weight of a polymer based on polypropylene modified with a grafting agent, wherein the grafting agent is selected from the group consisting of acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid or esters thereof, maleic anhydride, itaconic anhydride and combinations thereof.

42. - The polypropylene resin composition of claim 38, wherein the organic fiber is randomly dispersed within said polypropylene-based polymer.

43. - The polypropylene resin composition of claim 42, wherein the organic fiber is a polyalkylene terephthalate.

44. - The polypropylene resin composition of claim 43, wherein the organic fiber is polyethylene terephthalate. 45. - The polypropylene resin composition of claim 44, wherein the size of said talc is from about 1 to about 100 microns. 46.- The polypropylene resin composition of claim 45, wherein the molded article of said composition has a flexural modulus of at least about 2,586 GPa.